Howwie, regarding the 3rd party, etc
I agree with you. I was trying to be careful to not allow her version to affect mine (by first recalling my version silently before she continued recalling hers)
But to research it properly, we need third parties, etc.
My example wasn't controlled enough at all

Perhaps just writing down the journals as private entries online, and after both are up, turning them public for all to see?

About my wife and me participating:

Like I've mentioned before, my wife isn't really... focussed... when it comes to stuff like this.
She has to be 'in the zone', 'zenlike' and all that stuff

I've been trying to get her to repeat what she did since that day, and she's only once been like that. And I wasn't dreaming

So.. while the concept is sound, it's gonna be hard to do in practice